It's not just a battle over liberal or moderate policies. In many cases, the White House hopefuls largely agree on the end game but differ on how to get there, and how quickly. Sens. Bernie Sanders of Vermont and Elizabeth Warren of Massachusetts have set the pace. He's pitching an economic and political "revolution," while she is calling for "systemic change" to everything from health care to who pays for a college education.
"Let's have the big fight," Warren said in an interview. "The big fight is easier to win because people see it would be transformative." Other Democrats argue the kind of sweeping changes Warren and Sanders are pitching are too unrealistic, too costly or too disruptive to happen quickly. They often back the same concepts — particularly a "Medicare for all" health care system — but temper their support with what they see as a dose of reality.
During a recent campaign stop in New Hampshire, New Jersey Sen. Cory Booker told a voter there was a "hard truth" about pursuing a single-payer health care system: It might not get through Congress. The emerging divide is at the heart of Democratic deliberations over how to defeat President Donald Trump in November 2020. Could a more pragmatic politician win back some moderate voters in states like Michigan, Wisconsin and Pennsylvania who tilted the election toward Trump in 2016? Or does the Democratic path to victory lie in energizing turnout among liberals and young voters who weren't enthusiastic about the party's last nominee, Hillary Clinton?
In most recent presidential campaigns, Democrats have rallied around moderates and candidates who billed themselves as consensus builders: Clinton in 2016, Barack Obama in 2008 and John Kerry in 2004.
"It is the intuition of a majority of Democratic voters that a candidate who stresses ideas that are practical and realistic has a better chance of winning than a candidate who has ideas that are big and bold," said Geoff Garin, a Democratic pollster.
Implicit in the posture of candidates like Warren and Sanders is a belief that their own party has not gone far enough in pursuing economic policies that could provide more opportunity for middle and lower-income Americans.
"The problems in our economy and in our democracy go back decades," said Warren. She quickly added, "I'm not here to knock Democrats." But that hands-off approach to the rest of the Democratic field won't last.
In 2016, Sanders and Clinton battled over the same question of how fast and far to push economic change. Sanders cast Clinton as beholden to Wall Street interests, while she panned his ideas as impractical and wildly expensive. She won the primary but struggled to generate the same level of enthusiasm among some liberals and young voters as Sanders and lost to Trump in a stunning defeat.
Polling shows some of the ideas pushed by Sanders, Warren and others have broad support among Democrats, but they're not the only paths to desired results that voters say they could get behind. For example, 81 percent of Democratic voters say they favor a "Medicare for all" plan, according to a recent Kaiser Family Foundation poll. But when asked what Congress should be working on now, half of Democrats say lawmakers should focus their efforts on improving and protecting the federal health care law signed by Obama. Only 38 percent want lawmakers to focus on passing a national Medicare for all plan.
Other issues that could divide Democrats during the 2020 primaries include how to address the skyrocketing cost of college. During the 2016 campaign, Sanders pledged to make public colleges free, a dramatic revamping of the nation's higher education system. The following year, he and Warren co-sponsored a bill that proposed free tuition at four-year colleges for families earning less than $125,000 a year and no tuition at all at community colleges. The legislation, which gained no traction in a Republican-controlled Congress, would have provided $47 billion per year to states to eliminate tuition costs, leaving states to come up with another $23 billion annually on their own.
That kind of sticker shock has other candidates reluctant to sign on. "I am not for free four-year college for all, no," Minnesota Sen. Amy Klobuchar said in a CNN town hall. "I wish — if I were a magic genie and could give that to everyone and we could afford it, I would.
Candidates proposing big-ticket agenda items are already facing questions about how they'd get their ideas through Congress. That's prompting a debate over whether presidential candidates would support controversial moves that would remove a key hurdle to passing legislation.
Warren and New York Sen. Kirsten Gillibrand have indicated they would be open to changing the filibuster, a procedural tool that requires a supermajority of 60 votes to pass many big items instead of a simple majority in the Senate. Lowering the threshold would theoretically give a president a better chance of pushing through legislation.
Notably, Sanders is a proponent of keeping the filibuster alive, raising questions about how he would muscle through his proposals to reshape government.
AP writer Elana Schor and AP polling reporter Hannah Fingerhut contributed to this report.
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